Apparatus for mixing, agitating, abrading or crushing various materials



N 1965 HISAYOSHI KUBODERA 3,218,041

APPARATUS FOR MIXING, AGITATING, ABRADING OR GRUSHING VARIOUS MATERIALS 2 Sheets-Sheet 1 Filed Dec. 23, 1963 INVENTOR 'N 1965 HISAYOSHI KUBODERA 3,213,041 APPARATUS FOR MIXING, AG'ITATING', ABRADING OR CRUSHING VARIOUS MATERIALS 2 Sheets-Sheet 2 Filed Dec. 23, 1963 FIG. 8

FIG. 7

INVmR 'IWMI' I BY FIG. I2

FIG. IO

United States Patent 3,218,041 AiPARATUS FDR MIXING, AGl'lATlNG, ABRAD- ING GR CRUSHING VARIDUS MATERIALS Hisayoshi Kubodera, 1-1 Shihamitakoun-cho, Minato-ku, Tokyo-to, Japan Filed Dec. 23, 1963, Ser. No. 332,621 Claims priority, application Japan, Dec. 29, 1962, 37/ 59,444; May 23, 1963, SSS/29,936 July 3, 1953, 38/ 34,263, 38/34,264; Aug. 16, 1963, Bait/42,936; Oct. 26, 1963, 38/57,121

12 (Iiaims. (Cl. 259-81) This invention relates to an apparatus for mixing, agitating, abrading or crushing various materials, and more particularly to an apparatus of the above kind including a container for the materials to be treated rotatably mounted on a horizontal shaft.

Apparatus of this kind are known in which a material container is rotatably mounted on a horizontal driving shaft for rotation in a plane perpendicular to said shaft. In such apparatus, satisfactory mixing, agitating, abrading or crushing usually cannot be obtained even after an extended continuous operation because the materials in the container are driven only vertically through the container without being driven horizontally.

To obtain horizontal driving action, apparatus having a container obliquely extending from a horizontal shaft have been proposed. One of the proposed apparatus includes a straight cylindrical container obliquely supported at its central portion by a horizontal shaft for rotation thereabout, and another includes a V-shaped container rotatably mounted on a horizontal shaft, one hollow leg of the V-shaped container extending obliquely from the shaft toward one end thereof, the other hollow leg extending obliquely from the shaft toward the other end thereof, and the interiors of both the legs communicating with each other at the apex of the V-shaped container. In such apparatus with the obliquely extending container, materials contained therein can also be impelled horizontally as well as vertically with a wider extent of motion which results in more activated mixing since the container is sloped. The apparatus having the V-shaped container, as compared with the apparatus having the straight container, has the advantages of occupying less space, of being in good balance in operation, and of being easy to handle. However, in the apparatus with the V- shaped container, the following disadvantage is observed. When the apex of the V-shaped container descends below the horizontal shaft, the materials in both legs of the container rush into the apex portion at the same time and under the same condition, thereby colliding with each other and jamming, whereby the mixing of the materials is prevented. Thus, the materials in each leg of the V shaped container are subjected to mixing action independently of each other, and thorough and uniform mixing of all the materials cannot be obtained. For example, when a small quantity of a vitamin is thrown into one leg portion of the V-shaped container in which feed for domestic animals have been previously charged to be mixed, the vitamin cannot be mixed with the feed in the other leg portion of the V-shaped container even after an extended continuous mixing operation. This difficulty is also met when the apparatus is used as a ball mill for crushing the materials in the container or as an abrading machine which effects abrading operation by means of abrasives contained in the container. That is, the materials, balls or abrasives in the two legs of the V-shaped container cannot be interchanged with each other. In addition to this difiiculty, another difficulty arises in such appartaus. The balls or abrasives, having the tendency to move in advance of the materials or articles which are subjected to the action of the balls or abrasives, forcefully and 3,218,041 Patented Nov. 16, 1965 directly collide against each other at the apex portion of the V-shaped container, which collision may result in ball damage.

The above-mentioned apparatus with the obliquely extending straight container also has like difficulties. This type of apparatus generally operates more effectively than the ordinary apparatus having a container which is not obliquely supported since the materials in the apparatus with the obliquely extending straight container are impelled vertically and horizontally as previously described. However, in this type of apparatus, the materials of higher specific gravity tend to pass from one end of the container far from the shaft directly to the other end through the middle part of the interior of the straight container without any opportunity of being treated in the position inside the container casing near the horizontal shaft. This tendency may result in incomplete mixing because the materials to be mixed are not usually of the same specific gravity, most of them having somewhat different specific gravities. Such incomplete mixing can also occur when the materials to be mixed include different shapes, sizes or kinds of materials, which difference in shape, size or ind may cause differences in movability of the materials in the container.

Another type of apparatus has been heretofore known in which the material container is suitably rotated about a horizontal axis as well as a vertical axis for obtaining similar operation to that of the apparatus of this invention. In this type of apparatus, however, a perfect and effective operation cannot be obtained. This is especially true when the materials to be handled are of substantially different specific gravities.

Still another type of apparatus which is also well known includes an appropriate type of impeller rotatably disposed within a material container. In such apparatus, however, complicated mechanisms and much power are needed, and a number of stagnant corner parts are produced in operation in the container with the result that incomplete and nonuniform mixing of the materials occurs. Furthermore, this type of apparatus cannot be easily handled and is difficult to clean, which cleaning is an important problem for such apparatus.

Accordingly, a main object of this invention is to provide a novel apparatus for mixing, agitating, abrading or crushing various materials in which the aforementioned difficulties of prior art apparatus are overcome.

Another object of this invention is to provide a novel apparatus for mixing, agitating, abrading or crushing various materials which can effect more uniform, complete and effective operations than the heretofore known apparatus of similar kind.

A further object of this invention is to provide an apparatus as above stated which is simple in construction, easy to clean, capable of being fabricated of a wide variety of materials and capable of being constructed at a low cost.

According to this invention, the apparatus for mixing, agitating, abrading or crushing various materials comprises a relatively long material container supported at its longitudinally central portion rotatably about a horizontal axis, and a pair of ridged banks arranged on opposite inside walls of said container and extending in substantially transverse direction of both said container and said axis. Each of said banks has a pair of inclined surfaces and is disposed in symmetrical relation to each other with respect to the central point of said container. In addition, one of the banks is in a position offset a small distance from the axis of rotation of the container toward one longitudinal end of the container, and the other of the banks is in a position similarly offset toward the other longitudinal end of the container. Thus, the two banks are in U mutually staggered arrangement in the longitudinal direction of the container.

In the operation of this apparatus, the inclined surfaces of the pair of banks cooperate to guide therealong the materials in the upper half of the container in such a manner that the materials falling along the inclined surfaces of both banks are caused to move among each other in a mutually crossing manner. The materials thus intermixed by the mutually crossing movement then fall into the lower half of the container so as to collide against the side wall of the container. As a result of this colliding action, the materials are directed toward another direction in the lower half of the container, so that a second intermixing action occurs. The intermixing actions thus produced in the container are accompanied by horizontal movement of the materials, which horizontal movement of the materials is effective for the satisfactory mixing, agitating, abrading or crushing operation, as previously described. However, this horizontal movement of the materials in the container according to this invention is unique and is distinctly different from the horizontal movement in the heretofore known apparatus. The uniqueness of the apparatus of this invention resides in said banks which are symmetrically arranged in staggered positions to produce the crossing movements of the materials.

For a better understanding of this invention together with further objects and advantages thereof, reference is made to the following description of several preferred embodiments thereof taken in connection with the accompanying drawings, in which:

FIG. 1 is a fragmental front elevation, in vertical section, of an embodiment of this invention, the container thereof being in vertical position;

FIG. 2 is a side elevation of FIG. 1;

FIG. 3 is a fragmental front elevational of another e r.- bodirnent of this invention, the container thereof also being in vertical position;

FIG. 4 is a side elevational of FIG. 3;

FIG. 5 is a fragmental front elevation of another embodiment of this invention, the container thereof also being in vertical position;

FIG. 6 is a fragmcntal front elevation of still another embodiment of this invention, similar to that shown in FIG. 5, the container thereof also being in vertical position;

FIG. 7 is a fragmental front elevation, in vertical section, of a further embodiment of this invention, the container thereof also being in vertical position;

FIG. 8 is a side elevation of FIG. 7;

FIG. 9 is a fragmental front elevation of another embodiment of this invention, the container thereof also being in vertical position;

FIG. 10 is a plan View of FIG. 9;

FIG. 11 is a front elevation of still another embodiment of this invention; and

FIG. 12 is a plan view of FIG. 11.

Referring now to FIGS. 1 and 2, there is shown one embodiment of this invention. The apparatus shown in these figures includes a material container ll rigidly sccured at its central portion on a horizontal shaft 7 for rotation about a horizontal axis AB and closed at its longitudinal ends by covers 5 and 6. The material container it is, as shown, in the form of a relatively long cylinder. On opposite inside walls of the container 1 are rigidly secured a pair of opposite banks id and if of triangular cross-section, which banks it) and Ill extend transversely with respect to both the container 1 and the horizontal shaft '7 and have inclined surfaces, one surface of each bank and one surface of the bank being in parallel relation to each other. The bank if) on the left hand side of the container 1 as shown is in a position offset a small distance from the horizontal axis A-B toward one longitudinal end of the container 1 and has a pair of inclined surfaces 55 and do, while the other bank if on the right hand side of the container 1 is in a position offset a small distance from the axis AB toward the other longitudinal end of the container 1 and has a pair of inclined surfaces 9 and 90, these banks 10 and if being of the same dimension and shape and in symmetrical relation to each other with respect to the center X of the container ll. Thus, the interior of the container 31 is divided into two chambers 2 and 3 intercommunicated by the space between the two banks.

in operation, when the container 1 is rotated about he horizontal axis AB through the shaft 7 by suitable driving means (not shown), the materials charged in the container It move from the chamber, 2 into the chamher 3 with half a rotation of the container 1 and move back from the chamber 3 into the chamber 2 with the succeeding half a rotation. Thus, the materials undergo a reciprocating movement between the chambers 2 and 3 for one rotation of the container 1. When the container ll begins to rotate from the position shown in FIG. 1, the materials in the chamber 2, which is shown in the lower position, are raised as the rotation proceeds and then descend into the other chamber 3 as the container 1 rotates beyond the horizontal position thereof. In this descending movement of the materials, the materials on the left hand side of the chamber 2 are guided by the inclined surface S or" the bank l'ii to flow rightwardly, and the materials on the right hand side of the chamber 2 are guided by the inclined surface 9 of the bank 13. to flow leftwardly. in such a condition the first material flow from left to right is directed into the second material fiow flowing from right to left below the first mate rial flow, whereby intermixing action between both material flows takes place. This intermixing action causes thorough agitation and mixing of the material particles. The intermixed material flow including the first and second flows then fiows leftwardly into the chamber 3 of the container 1 and is directed rightwardly by the left side wall of the chamber 3 of the container. Thus, a second intermixing action occurs in the chamber 3.

In the succeeding half rotation, the first material flow fiowing leftwardly along the inclined surface 911 of the bank ll is directed into the second material fiow flowing rightwardly along the inclined surface do of the bank lltl, whereby the intermixing action as described above is caused, and then the intermixed flow is directed rightwardly. The intermixed fiow thus flowing rightwardly is then directed leftwardly, by the right side wall of the chamber 2 of the container 1. Thus, it will be noted that the material flow pattern in the former half rotation is symmetrical to that in the latter half rotation with respect to the center X of the container 1. The symmetrical arrangement of the banks 1t and 11 serves to effect a uniform operation for each of the reciprocating movements of the materials in the container 1. In addition to this feature, the passing of the materials through two bent paths defined by the pair of diagonally opposite banks 10 and 11 serves to produce an active movement of the materials having a horizontal component as well as a vertical component, even though the container 1 is rotated only about horizontal axis. Thus, a fast, effective and uniform mixing action can be carried out, even when the materials to be handled are of such a nature that the mixing thereof is difiicult because of the shapes, sizes or kinds of the particles of the materials or because of large differences of specific gravity of the materials to be mixed. The above described operation of the apparatus is similar also when the apparatus is employed for operations other than mixing, such as agitating, abrading or crushing.

The angle between the inclined surfaces 8 and 8a or 9 and 9a of the triangular cross-sectional banks 15 and fl is determined so as to allow all of the materials in the container 1 to pass along the surfaces 8, 8a and 9 and 9a. The shape and angle of the banks 10 and lil, if desired, may be modified so as to obtain the desired result according to the kind of operation. For example, the surfaces 8, 8a and 9, 9a may be inclined traversely with respect to the container 1 or may be curved, or the top portions of the banks and 11 may be waved or formed into comb-like shape. However, it is important to arrange and form the banks 10 and 11 into the center X of the container for obtaining the desired result. The extent of projection of the banks 10 and 11 toward the longitudinal axis of the container 1 is determined in accordance with the kind of materials to be handled and the kind of operation. If the extent of projection of the banks 10 and 11 is greater, the horizontal movement and therefore the intermixing action of the material will be greater to produce a better result. However, the inclined surfaces 8, 8a and 9, 9a will become longer, which longer surfaces will result in a longitudinally longer container 1 and, therefore, difficulty in its cleaning. The intermixing operation of the apparatus of this invention may be obtained when the top portions of the banks 10 and 11 do not reach the longitudinal axis of the container because the horizontal movement of the materials is accom partied by surplus energy. The distance between both the banks 10 and 11 is preferably made as small as possible in order to make the length of the container 1 small.

Referring now to FIGS. 3 and 4, another embodiment of the invention is shown as comprising a container 1 including a central cylinder 4 rigidly secured onto a horizontal shaft 7 in obliquely extending relation thereto for rotation about a horizontal axis A-B. At both ends of the central cylinder 4 of the container 1 are rigidly secured end cylinders 2 and 3 which extend in different directions from that of the central cylinder 4, these central and end cylinders extending in a zigzag form with their axes lying in the same plane. The end cylinders 2 and 3 are provided with covers 5 and 6 removably secured to the outer ends of the cylinders 2 and 3, thereby closing the container 1. The bent connections between the central cylinder 4 and the end cylinders 2 and 3 form a pair of banks 10 and 11 similar to the banks 10 and 11 shown in FIGS. 1 and 2. As in FIGS. 1 and 2, the banks 1%) and 11 are in symmetrical relation to each other with respect to the center X of the cylinder 1 and also have inclined surfaces 8, 8a and 9, 9a which also form the walls of the cylinders 2, 3, and 4.

in operation, the materials in the container 1 undergo a reciprocating movement between the end cylinders 2 and 3 as in the case of FIGS. 1 and 2. The intermixing operation of the apparatus is substantially the same as that of the apparatus shown in FIGS. 1 and 2 with the exception that the inclined surfaces 8, 8a and 9, 9a formed by the cylinder walls serve to produce a more active horizontal movement of the materials due to the longer faces thereof.

FIG. 5 shows still another embodiment of this invention in which the righthand side of the connecting portion between the central cylinder 4 and the end cylinder 2 is curved as shown at 12, and the lefthand side of the connecting portion between the central cylinder 4 and the end cylinder 3 is curved as shown at 13. These curved connecting portions 12 and 13 serve to guide the materials smoothly along the inside walls thereof and to eliminate the stagnant flows of materials which might occur without such curved portions. The elimination of stagnant flows will permit the materials to be uniformly intermixed and will facilitate the cleaning of the container. The bent connecting portions opposite to the portions 12 and 13 project sharply in the container 1 serving as the banks for guiding the materials for complete intermixing.

In FIG. 6, still another embodiment of this invention is illustrated. The container 1 of this embodiment is made by providing a relatively long cylinder, bending it at two portions thereof toward opposite directions, said two portions being situated longitudinally remote at the same distance from the center of the cylinder, and applying the covers 5 and 6 on the two ends of the cylinder. Thus, the apparatus shown in FIG. 6 is provided with a container 1 including a central cylinder 4 integrally connected with end cylinders 2 and 3 through curved bends. In this apparatus, the bent portions forming the banks It) and 11 are also curved smoothly, which are different from the sharply projecting banks It) and 11 shown in FIG. 5.

In the operation of this apparatus, the materials in the container 1 are intermixed in the same manner as aforedescribed in connection with FIG. 1. The smoothly curved connections of the container 1 produce smooth flows of materials and provide the advantage of easier cleaning of the container. However, it is diflicult, in the manufacture of this container, to make the curved portions forming the banks 10 and 11 project sufficiently to reach the central area of the container 1 to ensure efficient intermixing of the materials. This is true especially in the manufacture of the container of large capacity. Therefore, the containers of this type are preferably manufactured as the containers of small capacity.

Referring to FIGS. 7 and 8, there is shown a further embodiment of this invention. The apparatus shown is of the same construction as that shown in FIG. 5 with the exception that the container 1 is mounted on one side thereof on a shaft 7, and that the end cylinder 2 of the container 1 is detachably screwed into the central cylinder 4 of the container 1 as shown at 15. In this type of apparatus, the materials to be handled may be charged into the container 1 by placing them into the end cylinder 2 disconnected from the central cylinder 4 and then screwing the end cylinder 2 into the central cylinder 4. The discharge of the materials which have been treated may be carried out by the reverse procedure. Thus, the charging or discharging of the materials into or from the container 1 can be accomplished in a shorter time by a simple operation. The advantage of this type of apparatus also resides in that the materials are not scattered in the course of charging and discharging, and that the cleaning of the interior of the container is easier. Although the apparatus is shown as having one of the end cylinders detachably connected with the central cylinder, it is to be understood that both the cylinders 2 and 3 may be constructed to be detachably connectable. In such a case, both end cylinders 2 and 3 can be replaced by those of smaller capacity for adapting the container 1 to a smaller quantity of materials to be handled. Thus, the apparatus can be etficiently operated with appropriate quantity of materials contained therein. The apparatus as shown can be adapted for use in preparation of medicines in pharmacies or for domestic use.

In FIGS. 9 and 10, a still further embodiment of the invention is shown. The apparatus shown is of the same construction as that shown in FIGS. 3 and 4 with the exception that the container 1 is angularly displaced by an angle about the vertical axis thereof relative to the horizontal shaft 7. The angle of angular displacement is preferably 30 degrees. Such an arrangement of the container 1 relative to the horizontal shaft 7 reduces the horizontal extent of the container 1, thereby making possible reduction in the distance between the two bearings carrying the shaft 7. Too large an angle of said angular displacement, however, will result in less horizontal movement of the materials in the container and, therefore, should be avoided. In this type of apparatus, the materials raised to the higher position will be temporarily blocked up in the upper end cylinder of the container and thereafter will fall suddenly, which sudden fall of the materials will produce an active movement of the materials with better intermixing.

Since the power needed for the rotation of the container 1 is mainly used for raising the materials to the higher position and the falling materials participate in rotating the container, it is desirable to arrange two or more containers in mutually crossed or juxtaposed arrangement on the same horizontal shaft. By such crossed arrangement of the containers, the power required may be uniformly distributed and reduced.

F165. 11 and 12 show one example of such arrangemerit of the container it in elevational and plan views. In this arrangement shown, two containers are mounted on the same shaft in mutually perpendicular orientation, the difference in phase angle of the rotation between the containers being 90 degrees.

From the foregoing description, it will be apparent that the apparatus according to this invention can be used in cases where complete and uniform operations are dithcult to obtain. Such ditlicult cases are, for example, the mixing of tungsten (or tungsten carbide) and copper powder for producing sintered metal, the mixing of iron powder and magnesia for producing magnesium, and the mixing of a small quantity of vitamins or penicillin with foodstuffs for animals.

The apparatus of this invention, as above described, may also be advantageously employed for crushing operations by balls placed in the rotating container or for abrading operations by abrasives charged into the rotating container with the articles to be abraded. in these operations with conventional apparatus, the balls are subject to wear on the same faces therefore and consequent forming into ellipsoidal form and do not work on whole surfaces thereof. However, when the apparatus of this invention is used for such purposes, the balls or abrasives are uniformly distributed throughout the interior of the container and undergo both horizontal and vertical movement, and, therefore, uniformly crushed materials or articles uniformly abraded over the whole surfaces thereof can be obtained in a shorter time. In these crushing or abrading operations, the balls or abrasives are preferably charged into the container in a quantity occupying over a half of the interior volume of the container. The charge of the balls or abrasives to such an extent serves to prevent them from directly impinging against each other.

On the other hand, in the mixing operation, the materials are preferably charged into the container to an extent which does not exceed a half volume of the container, since the entire quantity of materials in the container must be passed between the pair of banlts for satisfactory mixing. The mixing operation according to this invention, however, may be carried out, even when the container is charged with a quantity of materials exceeding a half volume of the container.

in the operation of the apparatus according to this invention, excessive speed of rotation of the container will exert a centrifugal force on the materials, whereby they may be prevented from falling. Accordingly, the speed of the container should be so determined as to produce the most efficient operation according to the nature of the materials and the kind of operation to be performed.

The rotation of the container, if desired, may be of varying speed. In such a case, the rotation may be accelerated in the course of the raising of the materials in the container and may be retarded or stopped at the uppermost position. When the container is rotated at such a varying speed, the materials will reach the uppermost position with only a small amount thereof falling to the lower part of the container, and will suddenly fall from the uppermost position, which sudden fall of the materials will improve the unique intermixing effect of this invention.

The container to be employed according to this invention, may be of any cross-section, for example, circular, elliptic, rectangular or polygonal. The corner portions of the container are preferably rounded so as to ensure smooth and active flow of the materials and the easy cleaning of the container. if desired, the con tainer may have a stepped part in the path of the ma terials to produce a pulsated flow of the materials, or it may be provided with suitable linings. in addition, the container may be of transparent construction for facilitating the inspection of the interior thereof, or it may be of double wall construction for passage of heating or cooling mediums therebetween. Furthermore, the container may be provided with a discharge opening at the level just below the horizontal shaft and a charge opening at the level just above the horizontal shaft and a receiving tanlt adapted to receive the material discharged from said opening.

it should be understood, of course, that the foregoing disclosure relates to only preferred embodiments of the invention and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

El. An apparatus for mixing, agitating, abrading or crushing various materials, comprising a relatively long material container rotatably supported at its longitudinally central portion about a horizontal axis, a pair of inwardly projecting ridged banks arranged inside said container on opposite sides thereof extending in substantially transverse direction of both said container and said axis, each of said banks having a pair of inclined surfaces and being disposed in symmetrical relation to each other with respect to the central portion of said container, one of said banks being in a position displaced a certain distance from the axis of rotation of the container toward one longitudinal end of said container, the other of said banks being in a position displaced in the same manner toward the other longitudinal end of the container and, at least one lid on said container for insertingmaterial therein.

2. An apparatus for mixing, agitating, abrading or crushing various materials, comprising a relatively long material container rotatably supported at its longitudinal central portion about a horizontal axis, and a pair of inwardly projecting ridged banks arranged inside said container on opposite sides thereof extending in substantially transverse direction of both said container and said axis, each of said banks having a pair of inclined surfaces and being disposed in a symmetrical relation to each other with respect to the central portion of said container, one of said banks being in a position displaced a certain distance from the axis of rotation of the container toward one longitudinal end of said container, the other of said banks being in a position displaced in the same manner toward the other longitudinal end of the container, said material container being of cylindrical form having a straight vertical side wall and removable covers at both longitudinal ends thereof, said pair of banks projecting from said side wall.

3. An apparatus for mixing, agitating, abrading or crushing various materials, comprising a central cylinder rotatably supported at its central portion about a horizontal axis of rotation and extending obliquely in relation to said axis, an end cylinder connected to one end of said central cylinder in communicating relation thereto and extending in substantially transverse direction to said central cylinder, and another end cylinder connected to the other end of said central cylinder in communicating relation thereto and extending in substantially transverse direction to said central cylinder, said central cylinder and both end cylinders forming a material container closed at both ends thereof, both said end cylinders being in symmetrical relation to each other with respect to the central point of said central cylinder.

The apparatus according to claim 3, wherein the connecting portions etween said central cylinder and said end cylinders are rounded on the convex sides of said portions.

5. The apparatus according to claim 3, wherein said material container includes a central and end cylinders which are integrally united by cylindrical bent sections.

6. The apparatus according to claim 3, wherein at least one of said end cylinders is detachable from said central cylinder.

7. The apparatus according to claim 3, wherein said material cylinder is in an angularly displaced position about its longitudinal axis in relation to the horizontal axis of rotation.

8. An apparatus for mixing, agitating, abrading or crushing various materials, comprising a plurality of material containers rotatably arranged about a horizontal axis of rotation, each of said material containers including therein a pair or ridged banks disposed on opposite inside walls of said container and extending in substantially transverse direction of both said container and said axis, each of said banks having a pair of inclined surfaces and being disposed in symmetrical relation to each other with respect to the central point of said container, one of said banks being in a position displaced a certain distance from the axis of rotation of the container toward one longitudinal end of said container and the other of said banks being in a position displaced in the same manner toward the other longitudinal end of the container.

9. The apparatus according to claim 1, wherein said banks are inclined in the transverse direction of the container.

10. The apparatus according to claim 1, wherein the ridge portions of said banks are waved.

11. The apparatus according to claim 1, wherein the ridged portions of said banks are formed in comb-like shape.

12. The apparatus according to claim 1, wherein said inclined surface of the banks are curved.

References Cited by the Examiner UNITED STATES PATENTS 2,021,261 11/1935 Moore 51--164 2,025,974 12/=l935 Fritz 259-15 1 2,138,550 11/1938 MacLellan 259-44 2,302,400 11/1942 Stone 259-151 FOREIGN PATENTS 1,072,452 12/1959 Germany.

CHARLES A. WILLMUTH, Primary Examiner. 

1. AN APPARATUS FOR MIXING, AGITATING, BRADING OR CRUSHING VARIOUS MATERIALS, COMPRISING A RELATIVELY LONG MATERIAL CONTAINER ROTATABLY SUPPORTED AT ITS LONGITUDINALLY CENTRAL PORTION ABOUT A HORIZONTAL AXIS, A PAIR OF INWARDLY PROJECTING RIGEDC BANKS ARRANGED INSIDE SAID CONTAINER ON OPPOSITE SIDES THEREOF EXTENDING IN SUBSTANTIALLY TRANSVERSE DIRECTION OF BOTH SAID CONTAINER AND SAID AXIS, EACH OF SAID BANKS HAVING A PAIR OF INCLINED SURFACES AND BEING DISPOSED IN SYMMETRICAL RELATION TO EACH OTHER WITH RESPECT TO THE CENTRAL PORTION OF SAID CONTAINER, ONE OF SAID BANKS BEING IN A POSITION DISPLACED A CERTAIN DISTANCE FROM THE AXIS OF ROTATION OF THE CONTAINER TOWARD ONE LONGITUDINAL END OF SAID CONTAINER, THE OTHER OF SAID BANKS BEING IN A POSITION DISPLACED IN THE SAME MANNER TOWARD THE OTHER LONGITUDINAL END OF THE CONTAINER AND, AT LEAST ONE LID ON SAID CONTAINER FOR INSERTING MATERIAL THEREIN. 